Wireless telecommunications networks (e.g., Long-Term Evolution (“LTE”) networks) typically utilize multiple systems and corresponding interfaces for charging functions. For instance, one system (e.g., an Offline Charging System (“OFCS”)) may track subscribers' usage for the purpose of billing, generating statistics, and/or other functions that are not considered “real time” functions. On the other hand, another system (e.g., an Online Charging System (“OCS”) may facilitate the “real time” tracking of subscribers' usage, which may be useful in alerting subscribers (e.g., in scenarios where a particular subscriber is approaching his or her allotted voice call minutes or data, etc.) and/or performing other “real time” charging functions. These systems may each have various interfaces with elements of an LTE network, such as a Serving Gateway (“SGW”), Packet Data Network (“PDN”) Gateway (“PGW”), and/or one or more other elements.